“We’ve been using a ‘cold’ beam laser to remove a thin layer from the surface of the crystals,” Dr Ubide said.

“Then this tiny amount of material is put into a mass spectrometer, an instrument that measures the composition of ‘trace’ elements, reading elements that might weigh lower than 0.1 per cent of the original object.

“We found that the changes in the trace elements in these crystals are extremely sensitive to the processes that take place inside volcanoes, like magma storage and cooling, magma mixing, magma transport and magma’s ascent to the surface.

“It’s an amazing snapshot of what is happening inside volcanoes, providing key insights into their internal plumbing system and helping us better understand these incredible natural wonders.”